Lubricating composition



Patented Nov. 23, 1943 LUBRICATING COMPOSITION John G. McNab, Crani'ord, and Carroll J. Wilson and Carl Winning, Westfield, N. J assignors to Standard Oil Development Company, a corporation of Delaware No Drawing. Application December 31, 1941, Serial No. 425,128

17 Claims.

This invention relates to lubricating oils and methods of preparing the same, and more particularly to mineral lubricating oil compositions for use as crankcase lubricants in internal combustion engines.

Because in recent years the requirements for lubricating oils for gasoline and Diesel engines have steadily been made more stringent, it has been proposed to add various ingredients to these oils to improve their behavior in such service. One purpose of these ingredients is to impart detergency to the oils, thus bringing about greater engine cleanliness and avoiding ring sticking, carbon formation and varnish deposition. Certain of these ingredients also impart oxidation resistant properties to oils, thereby tending to inhibit the development of corrosive ingredients in, such oils. Corrosion-preventing addition agents are particularly required when the oil is to come in contact with the newer type of alloys 01' silver and cadmium and of copper and lead, which are now widely used as bearing metals.

Various metal-containing organic compounds which also contain sulfur in a lower state of oxidation have been found particularly useful as detergents as well as corrosion-preventing agents.

. Such compounds include metallic thiophenolates and thioxanthates, metallic derivatives of various phenol sulfides and disulfides, etc. In use, the effectiveness of these compounds is graually spent. The detergent capacity becomes exhausted as deterioration products, soot, dirt, varnish, etc., accumulate in the lubricant and saturate the adsorptive power of the additive. In engines equipped with a filter, the latter tends to remove the additive, particularly when the additive is adsorbed on contamination products which are strained out by the filter. The oxidation processes which are underway in an oil during use operate upon the antioxidant functions of the additive and thus also contribute to its exhaustion. The oxidation of the oil also creates insoluble substances which the detergent is called upon to adsorb, thus lessening its capacity for dispersing contamination products which enter the oil, and acidic substances are also formed which may react directly with the detergent to destroy its eflicacy. When the detergent is employed also to impart corrosion resistant properties to the oil, the above degradation phenomena all hasten to break down this corrosion resistance.

It is apparent from the foregoing observations that any auxiliary agent capable of stabilizing the oil in the presence of the detergent should materially extend the benefits obtained with the latter. It should also afford protection against corrosion after the detergent has become saturated with dispersed materialsor removed by an oil filter. However, the expected additional benefits are not realized when certain wellknown corrosion inhibitors and stabilizing agents, such as sulfurized sperm oil, dibenzyl disulfide, triamylphenyl phosphitc and the like, are added to the oil containing a metallic detergent agent. In some cases, in fact, the corrosive effect is even increased by adding such compounds.

It has now been found, in accordance with the present invention, that very satisfactory results may be secured by adding to the oil, in addition to the metallic sulfur compound, a tertiary aliphatic ether of a phenol, this compound being more particularly defined in the description which follows. This combination of addition agents provides for detergent action in the early stages of the use of the oil, as well as continued corrosion inhibiting effect after the metallic detergent compound has been removed to some degree by the filter, and whether a filter is or is not used there is a distinct advantage in using the combination of additives here described, since the corrosion of metal surfaces and the formation of deposits on engine parts are notably reduced.

The addition agent which is to serve, in accordance with this invention, as the detergent agent as well as a corrosion preventing agent in the early stages of use, may be defined as an organic compound containing a metal or a basic radical, such as ammonium, sulfonium or phosphonium, etc., and containing also at least one atom of sulfur in dilvaient form. There may be more than one atom of sulfur in the molecule, but at least one atom of sulfur is divalent and is linked either directly to carbon or to another sulfur atom which in turn is linked directly to carbon. This class of metal-containing sulfur compounds includes metallic derivatives of such organic compounds as 'the mercaptides, thicphenolates, xanthates, thioxanthates, metallic derivatives of various sulfides and disulfides of phenols, etc. This class of addition agents also includes the corresponding compounds in which sulfur is replaced by selenium or tellurium.

Typical general classes of metal sulfur compounds included within the above definition are the following:

A. Compounds in which a metal is attached to sulfur 3. Metal salts oi thiocarboxyiic acids 4. Metallic xanthates s a-o-Ji-s -M 5. hletallic thioxanthates s a-s-ti-su 8. Metallic thiocarbonates other than xanthates R80(O)BM noomsm 7. Metallic thiocarbamates n I o \alLwa f 8. Metallic dithiocarbamates B. Sulfur compounds in which a metal is attacked to elements other than collar 1. Natalia-organic compounds 8 s Bld -SH Ru -5M 2 Metallic soaps o o n-s-no msw 3. Metallic derivatives oi thioethers R'SHlC ones 17- RSMB In all of the above formulas R, R, eta, represent aliphatic or aromatic radicals and M, M, etc., represent metals or other basic acting units, such as basic radicals. If desired, S may be replaced by Se or Te.

In any of the various types of sulfur compounds named above any of the aromatic or aliphatic radicals may contain further substituent atoms or groups, such as oxygen, sulfur, halogen, nitrogen or phosphorus atoms, as well as groups such as alkyl, aralkyl, aryl, cycloalkyl, OH, SH, NHz, NH (alkyl), -N (aikylla, -0 (alkyl), -O (aryl), B (allavl), S (aryl), 00 (alkyl), -CO (aryl), --CHO, and COO (alkyl).

A preferred group of compounds for use in the present invention is that containing the radical defined by the formula MXAr(R) Sn-(R) Arm in which M is a metal, X is oxygen or sulfur, Ar is an aromatic nucleus, R is an organic group,

' B is sufur and n is an integer, 1 to 4. Ar may represent a single benzene ring or a condensed ing system and the substituents R. may be alkyi, aryl, aralkyl, aikaryl, or substituted groups and may occur more than once in each ring. The group 8 may have any 01' the following conflsuratlons:

The radicals represented by R in the above formula should be or sufllcient size to impart adequate oil solubility to the compounds and such alkyl radicals as butyl, amyl, diisobutyl, dscyl. cetyl, and steal-y] have been found satisfactory. Whenever the diisobutyl group i mentionedin this specification, the tetramethylbutyl radical. formed by polymerizing isobutylene, is meant,

When the phenolic groups are alkyiated with petroleum oleflnic hydrocarbons, such as r iinery gases and the like, the resulting produc may comprise a mixture of compounds with different sizes of alkyl groups. Mixtures of metal-containing sulfur compounds prepared from such mixed alkyl groups are also contemplated in this invention.

In some cases the phenolic compounds may be alirylated with long chain groups such as those derived from petroleum wax or an ester wax. In such cases one wax group may be attached to each and group or several aryl groups may be attached to one wax group at several point along the chain, as represented below.

It should" be understood, of course, that these are merely examples of the types of compounds which can be formed during alkylation and that the invention is not to be limited by this description.

Among the compounds falling in the preferred class those most frequently used are the sulfides or disulfldes of metallic derivatives 01' phenols, for example, barium bis-(diisobutyl phenoxy) sulfide, magnesium bis(tertiary amyl phenoxy) sulnde, and the various metallic salts of alkylated hydroxybenzyl sulfide and alkylated bis(hydroxybenzyl) disulilde.

The metals of the above described class of compounds may be selected from any of the metallic Groups. but are preferably members of groups I, II, III, IV or VIII of the periodic table. Particularly desirable are group II metals, barium, calcium. magnesium, and zinc, and, in addition, cobalt, nickel, and tin. In place of the metals there may be substituted any of the well-known basic radicals, such as ammonium or the various onium groups, such as the quaternary ammonium base radicals and the corresponding sulfonium, phosphonium, arsonium or pyridonium radicals and the like.

These compounds may be prepared by any wellknown methods. For example, barium bis-(diisobutyl phenoxy) sulfide may he prepared byalkylating phenol with diisobutylene, followed by treatment with sulfur chloride to form th thioether and finally saponiflcation with barium hydro'xide to form the salt. The invention is not to be limited by any method oi preparing these additives, however.

The following is a description 01' one method which has been used for preparing barium bis- (diisobutyl phenoxy) sulfide (barium salt of diisobutylhydroxy phenyl sulfide).

Exnlrrll A 31% solution or diisobutyl phenol in chloroform, containing a total of 217 lbs. otdiisobutyl phenol, was placed in a reaction vessel. Over a period or 3. hours 80.6 lbs. of sulfur chloride, 861:, were added gradually, the temperature or the mixture being held at 20-25 C. Following this step, the. mixture was heated under reflux for two hours and the chloroform then removed by heating to 100? C. V blown with carbon dioxide for several neutral to pongo red paper.

The amount of diisobutyi hydroxy phenyl sulnde present in the reactor after the above procedure was estimated to be 238 pounds. About 395 lbs. of an extracted Mid-Continent lubricating all (about 52 secs. viscosity (Saybolt) at 210 F.) were pumped into the reactor and mixed with the hours until biisobutyl hydroxy phenyl sulfide. While agitation was continued, the temperature was raised to 210 F. and a stream of nitrogen under 2 lbs/sq. in. pressure was blown in at the bottom or the reactor. Then '75 lbs. of stearyl alcohol were added and the temperature raised to 230 F. Gradual addition of 185 lbs. of a technical grade or barium hydroxide octahydrate,

BMOH) 2.81120 was then begun, the temperature first being raised to 240 F. and the stream or nitrogen continued.

Alter about 85% (163 lbs.) or the barium hydroxide had been added (requiring 'aibout 6 hours) excessive roaming occurred, but it was found that this could be controlled by raising the temperature to 250' F1, whereupon the balance or the barium hydroxide was added. Following this, the batch was blown with nitrogen for one hour at 10 230' F. to remove all water. Four pounds of Hyflow filter aid were added and the mixture filtered at 260 R, yielding a concentrate of oil containing 40% of the barium salt of diisobutyl hydroxy phenyl sulfide and 10% of stearyl alcohol. Analysis indicated 9.02% barium, almost exactly the theoretical amount for a 40% solution of the barium salt of diisobutyl hydroxy phenyl sulfide, HMO-CsHa-Csfin) 2B.

The second addition agent, to be added to the lubricating oil base in addition to a metallim sulfur compound of the above described class, may be deilned'as an organic compound of the formula Mr where Ar is an aromatic nucleus, which may contain one or more benzene rings or a condensed ring system such as naphthalene and the like, R is an organic radical, R is a tertiary aliphatic radical, and n. is an integer indicating the number of radicals n which are attached to the nucleus. The R groups may be alike ordiiferent. The substituent group or groups R appear to be required to activate the ether group and enable the compound to perform its function. Included within the scope of the above formula are compounds in which one or more or the hydrogen atoms or the aromatic nucleus or 01' the radicals R and B may be replaced by substituent atoms. such as oxygen, sulfur, nitrogen, phosphorus or halogen, or groups, such as alkyl, arallql,

-S(aryl), -CO(all:yl), -CO(aryl), -CHO,

COOH, CO0(alkyl), as well as groups containing metals, such as -0M, --SM, -COOM,

CSSM, etc., or. in place of the metals, basic groups, such as the ammonium, suli'oniurn, phosphonium, and pyridonium base radicals. M represents a metal equivalent.

A more preferred group of compounds, falling within the class defined immediately above, are those having a benzene ring as the aromatic nucleus. Especially suitable are the compounds defined by the formula Finally, the product was in which R and R. are aliphatic radicals or hydrogen and R" is a tertiary aliphatic radical. An example of such a compound is the tertiary butyl ether of ortho tertiary butyl p-cresol.

Among other ethers which may be employed in this invention are the tertiary butyl ether of ortha tertiary butyl para isopropyl phenol, tertiary amyi ether of ortho tertiary amyl para isopropyl phenol, tertiary hexyl ether of ortho tertiary hexyl para isopropyl phenol, tertiary butyl ether of ortho tertiary butyl para isobutyl phenol, tertiary butyl ether of ortho tertiary butyl para ethyl phenol. tertiary butyl ether of ortho tertiary butyl para normal hexyl phenol, tertiary butyl ether of ortho secondary butyl para cresol, tertiary butyl ether of ortho normal butyl para cresol, tertiary butyl ether of ortho secondary amyl para cresol, tertiary butyl ether of ortho secondary butyl para ethyl phenol, tertiary butyl ether of ortho secondary butyl para normal butyl phenol, tertiary butyl ether of ortho secondary butyl para isobutyl henol, tertiary butyl ether of ortho normal butyl para hexyl phenol, tertiary amyl ether or ortho secondary butyl para isobutyl phenol, tertiary butyl ether of ortho secondary amyl para isobutyl phenol, tertiary butyl ether of 4-tertiary butyl alpha-naphthol tertiary amyl ether of Z-phenyl- 4-isobutyl phenol, tertiary butyl ether of 2,6- di(propylamino)-4-methyl phenol, tertiary butyl ether of ortho chlorohexyl para cresol, tertiary amyl ether of ortho tertiary amyl para cresol sulflde, tertiary butyl ether of 2-butyl-4-ethyl-6- chlorophenol, and tertiary hexyl ether of 2-decyl- 4-ethyl resorcinol.

A still further class of ethers which may be advantageously employed are those having long side chain groups, such as those derived from petroleum wax or an ester wax. In such cases one wax group may be attached to each aryl group or several aryl groups may be attached to one wax group at several points along the chain. For example. when long chain alkyl groups are introduced into the compounds, as by aikylation with halogenated paraffin wax, mono-halogenated wax tends to give alkylated phenyl ethers of the following types:

(.nmcs. w) on CHdCHh) HCmHlm) CH:

on OK on f l, CHaCHz-- H----CH:CH:

The above described tertiary aliphatic ethers of phenol may conveniently be prepared by reacting a phenol with a tertiary olefin, e. g., isobutene, or with a tertiary aliphatic alcohol, e. g., tertiary butyl alcohol, in the presence of a catalyst such as sulfuric acid. In general, the tem-. perature should be above that of the phenol being reacted. A satisfactory method for the preparation of the tertiary butyl ether of ortho tertiary butyl p-cresol, one of the preferred additives, is-as follows: p-Cresol is mixed with about 5% of its weight of 96% commercial sulfuric acid and agitated at about 70 C. while isobutene is bubbled through the mixture. After completion of the reaction, as indicated by the flow of isobutene from the gas exit, the reaction mixture is blown with steam and washed with hot water and dilute alkali until neutral. A high yield of an oily material is obtained, which readily crystallizes on cooling. The product may be recrystallized from hot alcohol. The same product may be obtained by reacting p-cresol with tertiary butyl alcohol. In this case the amount of sulfuric acid catalyst is preferably quite large, i. e., of the order of one mol of catalyst per mol of p-cresol. Temperatures from about 0 to about C. may be used, preferably from 25 to 40 C.

The lubricating oil base stocks of this invention may be straight mineral lubricating oils or distillates derived from paraflinic, naphthenic, asphaltic or mixed base crudes, or, if desired, various blended oils may be employed as well as residuals, particularly those from which asphaltic constituents have been carefully removed. The oils may be refined by conventional methods using acid, alkali and/or clay or other agents, such as aluminum chloride, or they may be extracted oils produced, for example, by solvent extraction with solvents of the type of phenol, sulfur dioxide, furfural, dichloro ethyl ether, propane, nitrobenzene, crotonaldehyde, etc. Hydrogenated oils or white oils may be employed as well as synthetic oils prepared, for example, by the polymerization of oletlns or by the reaction of oxides of carbon with hydrogen or by the hydrogenation ctcoal or its products. In certain instances cracking coal tar fractions and coal tar or shale oil distillates may also be used. Also, for special applications, animal, vegetable or fish oils or their hydrogenated or volotolized products may be employed, either alone or in admixture with mineral oils.

For the best results, however, the base stock chosen should usually be that oil which without the additive present gives the optimum performance in the service contemplated. Since one advantage oi the additives is that their use also makes feasible the employment of less satisfactory mineral oils or other oils, no strict rule can be laid down for the choice of the base stock. Certain essentials must of course be observed. The oil must possess the viscosity and volatility characteristics known to be required for the service contemplated. The oil must be a satisfactory solvent for the additive, although in some cases auxiliary solvent agents may be used. The lubrieatin oils, however they may have been produced, may vary considerably in viscosity and other properties depending upon the particular use for which they are desired, but they usually range from about 40 .to 150 seconds Saybolt viscosity at 210 F. For the lubrication of medium and high speed Diesel engines the general practice has been to use a lubricating oil base stock prepared from naphthenic or aromatic crudes and having a Saybolt viscosity at210 F. of 45 to 90 seconds and a viscosity index of 0 to 50. However, in certain types of Diesel service, and in gasoline engine service, oils of higher viscosity index are often required, for example, up to or 100, or even higher, viscosity index.

In addition to the materials to be added according to the present invention, other agents may also be used such as dyes, pour depressors, heat thickened fatty oils, suli'urized fatty oils, organo metallic compounds, metallic or other soaps, sludge dispersers, antioxidants, thickeners, viscosity index improvers, oiliness agents, resins, rubber, olefin polymers, voltolized fats, voltolized mineral oils, and/or loidal solids such as graphite or zinc oxide, etc. Solvents and assisting agents, such as esters, ketones, alcohols, aldehydes, halogenated or nivoltolized waxes and coltrated compounds, and the like, may also be em- Played.

Assisting agents which are particularly desirable are the higher alcohols having 8 or more carbon atoms and preferably 12 to carbon atoms. The alcohols may be saturated straight and branched chain aliphatic alcohols such as oetyl alcohol, CsHnOH, lauryl alcohol, CnHaeOI-I. cetyl alcohol, CisI-InOI-I, stearyl .alcohol, sometimes referred to as octadecyl alcohol, CIIHIITOH, and the like; the corresponding oleflnic alcohols such as oleyi alcohol; cyclic alcohols, such as naphthenic alcohols; and aryl substituted alkyl alcohols, for instance, phenyl octyl alcohol, or octadecyl. alcohol or mixtures of these ya'flous'alcoholawhichmaybepureor substantially pure'synthetic alcohols. One may also use mixed naturally occurring alcohols such as those found in wool fat (which is known to contain a substantial percentage of alcohols having about 16 to 18 carbon atoms) and in sperm oil (which contains a high percentage of cetyl alcohol); and although it is preferable to isolate the alcohols from those materials, for some purposes the wool fat, sperm oil or other natural products rich in alcohols may beused per se. Products prepared synthetically by chemical processes may also be used, such as alcohols prepared by the olddation of petroleum hydrocarbons, e. g., parailln wax, petrolatum, etc.

Generally the amount of each 0! the additives oi the present invention in the finished lubricant composition should be between the approximate limits of 0.02 and 2.0%, and preferably between 0.1 and 1.0%, the exact amount to be used depending to a certain extent on the particular compounds used, the character of the oil base and the operating conditions of the engine in which the lubricant is to be used.

Typical examples of additive mixtures which may be employed in practicing this invention include the following: the tertiary butyl ether of ortho secondary amyl p-cresol with calcium tertiary amyl thiophenolate; the tertiary butyl ether of ortho tertiary butyl p-cresol with zinc lauryl mercaptlde; the tertiary butyl ether of ortho tertiary butyl p-isopropyl phenol with tin dicyclohexyl dithiocarbamate; the tert ary butyl ether of ortho secondary butyl -p-ethyl phenol with the barium salt oi wax-alkylated phenoxy thioether; the tertiary hexyl ether of ortho nbutyl' p-cresol with nickel amyl xanthate, the tertiary butyl ether of ortho tertiary butyl pcresoi with the barium salt oi bis-(diisobutyl phenoxy) sulfide; and the tertiary amyl ether of ortho n-butyl p-cresol with the aluminum salt oi thiooleic acid. Compositions in .which two or.

more metal compounds are used with one or more others or in which one metal compound is used nth two or more others are also contemplated in this invention. The clients of some of these additive mixtures on the corrosion resistance and engine performance oi oils in which they were blended are shown. in the examples given below.

The first two of the iollowing examples show the eilect of the use of a tertiary aliphatic ether 0! an aromatic compound upon the corrosion of copper-lead bearings when used in combination with a metal-containing sulfur compound in a lubricating oil, as compared with the use of several known corrosion inhibitors in combination with the same metallic sulfur compounds. In these examples the well-known corrosion inhibitors had only an adverse effect on the corrosive properties of the oil, while the ether compound aided considerably in preventing corrosion.

linux12 Samples oi oil blends containing, separately. well-known corrosion inhibitors as well as a tertiary aliphatic ether of the present invention, in addition to one or more of the metal-containing sulfur compounds 0! the present invention, as well as samples oi. oil containing the some metal sulfur compounds, but with the omission of the second corrosion inhibitor, were submitted to a bearing corrosion test in which the extent of weight loss of alloy bearings, due to corrosion by the oils, was determined. This test was conducted as follows:

500 cc. of the oil were placed in a glass oxidation tube (13" long and 2%" diameter) fitted at the bottom with a W bore air inlet tube perforated to lacllitate air distribution. The orldation tube was then immersed in a heating bath so that the oil temperature was maintained at 325 1". during the test. Two quarter sections of automotive bearings oi copper-lead alloy of known weight and having an area of sq. cm. were attached on opposite sides 0! a stainless steelrod which was then immersed in the test oil and ranted at 600 R. P. M., thus providing sumcient agitation of the sample during the test. Air was blown through the oil at the rate of 2 sable feet per hour. At the end of each hour fresh Marines were supplied and 15% at the oil in the oxidation tube was removed and a corrdlng amount of fresh oil was added. After the hearings were removed in each test, they were washed with naphtha and weighed to determine the amount of beams weight lost by corrosion. The tests were continued in each case until the cumulative wow loss of all the bearings tested with a given 08 blend was 50 milligrams.

A refined lubricating oil or S. A. E. 20 grade and consisting or an extracted Mid-Continent parailnic oil was blended with 0.5% of barium hie-(dflibliutylpheno sulfide, 0.5% of barium bia-(diisobutyl phenoxy) dlsulilde and 0.25% of stem! alcohol. A sample of this blend was submitted to tile above described test, as well as samples of the some blended, respectively, with 1% of film 017m 011, 1% of sulfurized spcrmoihmli of dibenzyl dlsulflde, and 0.5% of the tertiary sum ether of ortho'bertiam ml p-cresol. (m cites used in these nemies comprises synthetic oil: falling in the lubricating oil range prepared by polymerization oi isobutylene with boron fluoride) The results are shown in Table I, in which. the "bearing life" refers to the number of hourswhich elapsed to produce a cumulative bearing weight loss of 50 milligrams.

. Table I wifstet ryl alcohol B 011A 1. urisedpol meroil 7.0 Oilll i.% milurisedsfiggm oil.... a! Oil n+0. o dibcnsyl lllde a o (E) Oil A+0.5% tert.-l)utyl ether of ortho terL-butyl p-cmeol ll. 6

The results given in Table I clearly show that the variou sulfur compounds commonly advo- 6 assaow ExmruS binatlon of addition agents which constitutes the present invention.

Exaurn 4 Samples of a base oil of S. A. E. 30 grade, alone and mixed with one or more of the additives oi the present invention, were submitted to the corrosion test described in Example 2,

using copper-lead bearings as before and the re- In this example, a refined mineral lubricatina suits are shown in Table III.

Table III Cumulative bearing weight loss, milligrams on ihour Qhours lhours tours ohours ohours 7hours Sbours l2hours labours illhours can attest emu oltect attest clteet attest test an attest mm nmmmomaanac) 4 8 m 41 85 m an r stews mm v 35k a a s s 12 1c 19 24 as 155 (c) a tfigiz a 4 a a 1c is 18 23 81 180 (D) agfl n l 4 e a 11 1a is m as so 42 73 oil base of B. A. E. grade, consisting 01' of extracted Coastal oil and 0! parafllnic oil, was blended with 0.25% of barium bis-(diisobutyl phenoxy) sulfide, 0.25% of barium bis- (diisobutyl phenoxy) disuiflde and 0.125% of stearyl alcohol. Samples of this blend alone and with the addition oi 0.25% of triphenyl phosphlte were each submitted to a test similar to that described in Example 2. The results are shown in Table II, in which the actual cumulative loss in bearing weight at the end oi each second hour These data show that the corrosiveness of'the mineral oil is somewhat reduced by adding the barium salts of bis-(dlisobutyl phenoxy) sulfide and disulflde plus stearyl alcohol, the blend taking 18 hours to corrode the bearings as much as the mineral oil alone did in 6 to 7 hours. By adding to this compounded oil a small amount of a tertiary alkyl ether or the present invention the corrosiveness is still further reduced, the weight loss with this oil (oil 1)) in 24 hours not being as much as in 5 hours with the uncompounded oil.

durin the test is recorded. on the other hand, ii the same amount or ter- Table II Cumulative bearing weight loss, milligrams on 2 hours 4 hours ll hours 8 hours in hours 12 hours 14 hours it home latest Intent intact latest latest intact latest inteat bisdflsobut lunt!) (A) Hm e. s gn-sought; l

dlaum 9.1 ctearyi coho! 10 22 41 76 m :53 m p on A+0% trip earl plmll'aillto- I 17 m m It can be seen that the trlnhmyl phosphite actually increased the ccrrosivenees o! the compounded oil rather than decreased it, which is surprising in view of the known eilect or this additive as a corrosion inhibitor in the absence oi suitor-containing metallic compolmds.

In the following series of tests, described as Examples 4. 5, and 8, various oil blends containing, separately or in the same oil. the preerred addition agents of the present invention, were submlttedto tests similar to that described in Example 2, the modifications in each case being indicated below. The results shown indionly after four hour intervals and the area of each test hearing was 25 sq. cm. The cumulative weight losses at the end of the various four hour cate the advantageous use of the preferred comperiods are indicated m Table IV:

" Table IV cumin-five bmrlnr sh: ices, mum on 1 hours Ghoul-s 12mm iehcurs miwurs ililiours IBbours eflned inu'al lubrloa oil (8. A. I. I!) 1 353 (g il A hiigdzflmbntyl phones sulfide g g '0 1Q wudmllgtimjl dithiocarbamate l1 2 t 3321" mmm'tacza"sal;rt;a;ai;m""r.a;|5'

sulfide o o (c) on I'd-0.26% additive M 1 o o I Tertiary bury] other 0! crtho tertiary butyl p-u'eeoi.

cresol.

Exams: 6 Other oil blends were tested in the manner described in Example 2, except that in this case 10 (a) two copper-lead bearing halves and two cadmium-silver bearing halves were placed alternately on opposite sides of the stainless steel rod and immersed in the oil samples as previously described and the tests conducted for live hours. 5

Table V shows the total bearing loss in each case.

These data further demonstrate that the ether additive of the present invention inhibits the corrosiveness oi compounded oils toward alloy bearings. Similar results were also obtained in a different type of corrosion test as shown in Example '1. EM 1 Oil blends were also subiected to the standard Underwood bearing corrosion test. which was conducted as follows: 40

The polished bearings oi the Underwood machine were thoroughly abraded with emery cloth so that corrosion would proceed uniformly and then accurately weighed. The apparatus was filled with 1500 cc. oi the lubricant under test and the pump and heater started. The oil pressure was regulated to pounds per square inch by means of by-pass valves and maintained at this pressure throughout the test. As soon as 50 the temperature of the oil reached 275 F. the heater and pump were turned oil just long enough to put the already prepared and weighed bearings in place. Two copper-lead and two cadmium-silver bearing halves were used simultaneously in each test. At the end of hours the bearings were removed, cleaned with naphtha, dried and weighed. The weight loss was taken as a measure or the corrosiveness of the oil.

In Table VI are shown the results of tests using the above procedure. The base oil consisted of a conventionally refined Coastal oil having a viscosity or 55 seconds Saybolt at 210 F.

Table VI Beari weight loss, n fiiigrams Oil Cadmium- Copperlcad silver (A) Boss oil-14.57 cobalt bis-(tert.-amyl Hhcnorfigsulflda l0 0 AH. additiveM 4 l Tertiary butyl other of ortbo tertiary butyl p-cresol.

In the examples which follow there are given results of tests of several oil blends run in various engines operating under diii'erent degrees of severity. These examples serve further to show the advantages to be gained by using in a lubricating oil a combination of additives illustrating the present invention.

A mineral lubricating oil blend containing metal salts oi suliur compounds asdescrl'oed below and asimiiar blend containing in addition a tertiary alkyl ether of an alkylated phenol were each tested for 500 hours in a General Motors 3-cylinder Diesel engine. The ioilowing engine conditions prevailed in each test: speed, 20003. P. M.; power output, brake H. R: back pressure, 6 in. of mercury; water temperature, 180 F.; oil sump temperature. 230 F.; intake air temperature, F. Results obtained, expressed on a demerit rating system, are shown in Table VII. Bearing weight losses are also given. With regard to the engine demerit ratings, it should be borne in mind that the lower the value is, the better the engine condition.

Table VII Engine Co demerits lead on necting rod Ring weight sons loss (A) B.A..E.ii0basecil(3il%ertracted coastal +05% iinraiiinic) l i ina go e barium -(diisobut l pile )disuliide +0.16 stearyl hfilliprcma also 00 3.45 m (8) 0i! A+0.25% tort-Duty! other of ortbo tert.-butyl p-cresoi .i 1.75 3.29 86 These results show that the ether additive not only reduced the corrosiveness of the compound-= ed oil toward the alloy connecting rod bearings but also improved the detergent action of the oil as shown by the ring zone and valve condition an Emu 9 Similar engine demerit tests were conducted tor 168 hours in a Hercules Diesel engine at 1506 R. P. 51., with an oil temperature oi 210' F. and a water temperature oi 180 F. The results are shown in Table VIII.

Table VIII Engine demerits B in BB! g on Dam? Over am Piston "i ii sons skirts Mwimm (A) 8. A. E. 30 base oil (35% extracted coastal +65% h r a 83% barium 84 2 .50 3.18 1.35 in 4m 3%; ggiflg gsg'gggfi i hf 1:: 3.81 4, n 1.13 4. 42 1,110 1.96 no use e25 an on {+0.25% tert.buty1ethel' oiortho wtr i m a. 1,4; 4,09 m

In this engine also the ether additive reduced the tendency of the compounded oil to corrode thebearinlslndlmll'ovcdthecleanllnessof the engine. with the ether additive the engine condition was aubstmtlally no worse after 168 hours of operation than it was after only 84 hours of operarugiton w en the ether additive was not Other engine teata were conducted with a C. I. R. aimle cylinder engine at 1800 R. P. M. for 60 hours, the oil temperature being 200' F.

and the water temperature 200' F. The results are shown in Table II.

Here again the ether additive markedly improved the engine performance of the compounded oil, the lower demerit rating indicating that the engine was in a much cleaner condition.

In addition tobeing employed in crankcase and automotive engines, the additives of the present invention may also be used in light mineral oils such as spindle oils and textile oils, metal cutting oils, turbine oils. insulating and transformer oils, steam cylinder oils and greases. Also, aince these additives achieve their detergent eflect by modifying surface actlvity, their use in asphalt, road oils and waxes to improve wettmg and adhesive properties is also contemplated. Idkewlse, they may be added to liquid fuels to increase their wetting ability for metals, enabling them to displace moisture which might otherwise cause corrosion of containers, fuel lines, pump parts, and the like.

This invention is not to be considered as limited by any theory as to the action of the various additives nor by any of the examples mentioned or described herein which are given for illustrative purposes only, but is to be limited solely by the terms oi the appended claims.

we clam:

1. An organic composition containing a small quantity of an organic compound of the formula RaAI'OR' where Ar is an aromatic nucleus, R is an organic radical, R is a tertiary aliphatic radical and n is an integer, and a small quantity of an organic compound containing a salt-forming unit selected from the class consisting of metals and basic radicals and containing also the element sulfur, at least one atom of sulfur being in divalent form and linked directly to carbonor to an atom of sulfur which is. linked to carbon.

2. An improved lubricant which comprises an oil base, a small quantity of a compound or the formula where R is an organic radical, R is a ter iary asaaoiv aliphatic radical and: is an lutmenandiamall quantity of an t metal and his element alarmat least one atom of said sulfur beta: in dlvalenticrmanndinted directly to carbon ortoan'atomof where R and R are aliphatic '1!" la a tertiary aliphaticredtca'l. quantity of n organic c containing a metal selected from groups 1,11, III, IV, mums: the periodic table and containingalao the element sulfur, at least one atom of sulfur being in divalent form and linked directly to carbon'orto an atom oi sulfur which is linked to carbon.

4. A lubricant for internal combustim engines which comprises amineral'oll bue atimill llmtity of the tertiarybutyl-ether of ortho tertiary butyl p-cresol, and a small quantity cf in organic compound containing a metal selected from groups I, II, III, IV, and VIII of the periodic table and containing also the element suliur. at least one atom of sulfur being in divalmt form and linked directly to carbon or to an atom of sulfur which is linked to carbon.

5. A lubricant for mternal combustion engines which comprises a mineral oil base, a'ilmall quantity of an organic compound of the formula MXR(S) awhere M is a member of the group consisting of metals and basic radicals, X is a. member of the group consisting oi oxygen and sulfur and la tity of an Organic attached to a carbon atom which is in turn attacbed only to atoms of the group r hydrogen and other carbon atoms, R is member of the group consisting of aliphatic and faromatic radicals. and n is an integer, oneto our.

6. A lubricant for which comprises a internal combustion engines mineral oil base. a small quancompound of the formula where R and R are Ielected from the group consisting of hydrogen and aliphatic radicals lad R" is a tertiary aliphatic radical, and a lmall quantity or a compound of the formula MXArtR) -8s-(R) ArxM oxygen and sulfur, Ar is an aromatic nucleus, R is an organic group and n is an intescr. one to four.

7. A lubricant for internal combustion engines which comprises a mineral oil base, a small quarrtity of the tertiary butyl ether ortho tertiary butyl p-cresol and a small quantity of a salt of a metal of group II of the periodic table and a phenoxy sulfide.

8. A lubricant for internal combustion engines which comprises a mineral 011 base, a small quantity of the tertiary butyl ether of ortho tertiary butyl p-cresol and a small quantity oi barium bis-(diisobutyl phenoxy) sulfide.

9. A lubricant for internal combustion engines which comprises a mineral oil base. about 0.2% to about 2.0% 01' the tertiary butyl ether of ortho tertiary butyl p-cresol and about 0.02% to about 2.0% of barium bis-(diisobutyl phenoxy) sulfide.

10. A lubricant for internal combustion engines which comprises a mineral oil base, about 0.5% of barium bis-(diisobutyl phenoxy) sulfide, about 0.5% of barium bls-(diisobutylphenoxy) disulflde, about 0.25% of stearyl alcohol and about 0.5% of the tertiary butyl ether of ortho tertiary vbutyl p-cresol.

11. A lubricant for internal combustion engines which comprises a mineral oil base. a small quantity oi the tertiary butyl ether of ortho tertiary butyl p-cresol and a small quantity of zinc iauryl mercaptide.

12. A lubricant for internal combustion engines which comprises a mineral oil base, a small quantity of the tertiary butyl ether oi ortho tertiary butyl p cresol and a small quantity of tin dicyclohexyl dithiocarbamate.

13. The method oi cleansing and lubricating an internal combustion engine which consists in charging the said engine and operating said engine with a lubricant comprising a mineral oil base, a small quantity oi an organic compound of the formula where Ar is an aromatic nucleus, R is an organic radical, R is a tertiary aliphatic radical and n is an integer, and a small quantity of an organic compound containing a salt-forming unit selected from the class consisting oi metals and basic radicals and containing also the element sulfur. at least one atom of suliur being in divalent form and linked directly to carbon or to an atom of sulfur which is linked to carbon.

14. The method of cleansing and lubricatins' an internal combustion engine which consists in charging to said engine and operating said engine with a lubricant comprising a mineral oil base stock, a small quantity of an organic comp und or the formula where R. and R are selected from the group consisting 0! hydrogen and aliphatic radicals and R" is a tertiary slkyl radical, and a small quantity oi an organic compound containing a metal selected from groups I. II, III. IV, and VIII of the periodic table and containing also the element sulfur. at least one atom 01' sulfur bein in divalent form and linked directly to carbon or to an atom of sulfur which is linked to carbon. 15. The method of cleansing and lubricating an internal combustion engine which consists in charging to said engine and operating said engine with a lubricant comprising a mineral oil base, a small quantity of the tertiary butyl ether of ortho tertiary butyl p-cresol and a small quantity of barium bls-(diisobutyl phenoxy) sulfide.

16. A lubricant for internal combustion engines which comprises a mineral oil base, a small quantity oi the tertiary butyl ether or ortho tertiary butyl p-cresol and a small quantity oi a metal alkyl mercaptide.

17. A lubricant for internal combustion engines which comprises a mineral oil base. a small quantity oi the tertiary butyl ether of ortho tertiary butyl p-cresol and a small quantity of a metal aliphatic dithiocarbamate.

JOHN G. McNAB. CARROIL J. WILSON. CARI.- WINNING. 

